We hypothesize that decision-making and facial emotion recognition are impaired in ET patients due to frontal lobe dysfunction which may have consequences in daily social life. The first aspect can be assessed with the Iowa Gambling Task, a simple paradigm that simulates real-life decision-making. Briefly, players are given four decks of cards, a loan of $ 2,000 and asked to play so they can lose the least amount of money and win the most. Turning each card carries an immediate reward and sometimes an unpredictable penalty. Decks A and B are the most disadvantageous leading to an overall loss of money, while decks C and D are the most advantageous with an overall gain of money. In contrast to control subjects, patients with damage of the orbitofrontal or ventromedian cortex continue to perseverate with the bad decks, sometimes even though they know that they are losing money overall. The second aspect, i.e. the recognition of facial emotion can be assessed in a simple paradigm where patients have to choose the best fitting response among six facial expressions (happiness, sadness, fear, surprise, disgust and anger) that are presented in random order. All study subjects will be tested with the Benton Visual Retention Test to exclude impairment in visual perception, visual memory or visuoconstructive abilities.